The present invention disclosed herein relates to method for detecting the center of substrate by detecting edge position of a substrate, method for transporting a substrate based on calculated amount of position dislocation of the substrate supported on a transporting unit when transporting the substrate by the transporting unit, and a transporting unit for transporting a substrate and a substrate treating apparatus including the transporting unit.
Photo-lithography process in a semiconductor manufacturing process is to form a desired pattern on a wafer. Generally, photo-lithography process is carried out by a spinner local equipment, which is connected with an exposure equipment and conducts continuously a deposit process, an exposure process, and a developing process. This spinner local equipment performs sequentially or selectively a deposit process, a bake process, and a developing process.
These processes are performed sequentially in a plurality of process chambers. A substrate treating process, when a process is completed in one process chamber, transfers the substrate from the one process chamber to the another process chamber by using a separate substrate transporting unit and performs a substrate treating process in the another process chamber.
However, when transferring the substrate, the substrate may be supported on transferring unit at un-right position.
Therefore, before transferring the substrate, it is checked if the substrate is placed on the right position.
Generally, whether a substrate is on the right position or not could be determined by calculating a center position of the substrate as placed and comparing the calculated center position with a reference center position. However, calculated midpoint of substrate based on detecting a position on a substrate and detecting notch position at the same time becomes different midpoint from a real midpoint of a substrate and cannot determine whether it is placed on home point or not and has a problem of checking the amount of dislocation of a substrate and transporting it.